[BARC-List] Battery calculation help

[Scott Ehrlich]

I can look at battery catalogs and see various NiMH or NiCad batteries for
our radios, their voltages and mah ratings.  But if I want to put together
a homemade battery supply consisting of a 8 D-Cells = 12-volts, what
formula and authoritative source can I use to determine the maH rating for
my project?  I also want to compare how much current and amount of
operating time will last with fewer cells.

I also want to compare/calculate the mah rating with the amount of power I
will produce (granted I'll need to look up the current rating for my radio
- Yaesu VX-5R, transmitting at its various power levels).

I'd also like to compare the mah and voltage (# of batteries) among
various brands - Duracell, Engergizer, store-brand (CVS, Walgreens), etc.

Thanks for any leads.

Scott, WY1Z